1. Field of the Invention
The present invention relates to a method and apparatus for receivability test and reachability test of an explicit multicast packet and more particularly, to a method and apparatus for receivability test and reachability test by using an explicit multicast packet having at least one destination in order to effectively secure the communication between a sender node and a receiver node.
2. Description of the Related Technology
Generally, the receivability test on a network is a test to determine whether a receiver node can obtain function embodiments provided by a packet or protocol composed of a specific network protocol as a sender node intended.
The prior protocols requiring the receivability test inherently have their processes for negotiating embodiment functions of protocols. The process selects functions to be used and functions not to be used during communication before flowing user traffic between end-to-end through the embodiment function negotiation.
Generally, the reachability test on a network is a test to be determined whether a packet composed of a specific network protocol can reach to the intended receiver end through the conventional routing.
There is not needed an additional reachability test on the conventional network. The determination of reachability depends on the normal operation of the routing protocol. The routing protocol tests the reachability of network by use of HELLO packet with which a sender end and receiver node confirm the presence and state of each other.
Signal packet in a general concept is a packet used for negotiating the communication condition before the user traffic generated at the sender end reaches the receiver end, or for exchanging information by use of HELLO packet of the network routing protocol. But, the explicit multicast(hereinafter referred to as ‘xcast’) does not provide signal packet intentionally.
It is because the xcast routing itself has an inclination toward a unicast routing. Also, to exchange signal packet between the sender end and the receiver end implies that network maintains the record of communication state. Thus, to maintain the communication state between the sender end and the receiver itself can cause network load.
Here, the xcast that does not adopt signal packet is designed to maintain a simple structure, so development and arrangement can be easily achieved.
But, since the xcast does not provide signal packet, it loses a possibility of useful tests for confirm the network states such as receivability test and reachability test. Until now no methods for receivability test and reachability test of xcast are provided. Thus, there is no way for the sender end and the receiver end to perform a stable xcast communication.